Refrigerating system



Oct. 19, 1937. $.-RUPPRICHT REFRIGERATING SYSTEM J 7 Filed llarh 22, 1953 2 Sheets-Sheet 1 INVENTOR ATTORNEY Oct. 19, 1937. s, upp c -n' 2,096,065

REFRIGERATING SYSTEM Filed March 22, 1933 2 Sheets-Sheet 2 ATTORNEY Patented Oct. 19, 1937 aosaoes nnsnfasnamc ems-rm Siegfried Bupprlcht, Ne'w York, N. Y.

Application March 22, 1933, Serial No. 882,115

In Germanylllaroh 23, 1932 19 Claims. 7 (or 62-115) This invention relates to improvements in re-- frlgerating systems and has for an object the provision in a refrigerating system of apparatus A the pipe 6 and the branch pipe -1 to a thermofor storing'up refrigeration to take care of sud- 5 den or peak load demands exceeding the ca- ,pacity'of ,the compressor used for operatingthe refrigerating system. 4

A further object of the invention is the provision in a refrigerating system .of a main 're- -1o ceiver connected to the condenser oi'.. the-system, and an auxiliary condenser and receiver positioned between the evaporator and the suction' of the compressor and including means in the auxiliary receiver for by-passing liquid.

15 refrigerant thereto from the main receiver.

Another object of the invention is the provision in a refrigerating system for the storage of heat in a medium of different character than the medium which carries heat from one part 20 of the system to another.- I This isaccompllshed by providing the high side of the system with an abnormally large receiver and providing an auxiliary condenser and receiver between the evaporator and the suction 26 connection to the compressor, Automatic means is provided in the auxiliary receiver for by-' passing liquid refrigerant from the main. receiver to supply suilicient refrigeration therein to oflset the heat leakage through the insulating ail-walls surrounding the auxiliary condenser and receiver. The system also includes an automatic device for returning oil from the-auxiliary reclver to the crank case 'of the compressor.

v For describing and illustrating the invention, 35 one embodiment is shown in connection with-a freezing system in which the evaporator is flooded and the pump shown in Figure 2 is eliminated.

vided with an upper series ofpipes 2 and a lower a series ofpipes t Water entersthe series at the lower end 4 and is discharged therefrom at;

the upper endla. The lowerseries or: pipes" 8 55 form the evaporator 1 a refrigerating system Referring to Figure 1 an aerator l-ls 'proand the description thereofbe directed a; a direct expansion system. I

Liquid refrigerant from areceiver passes via static expansion valve 8, which is'con'nected t0 the lower end 9 of the evaporator 3. A thermobulb ill for controlling the expansion valve 8 is mounted in'heat exchange relation to the evaporator 3 at a-convenient 'po'intr A compressor l2, driven by a'motor-i3 by 10v means of a belt andpulley (not shown) .is"'provided with an oil vessel ll connected to the lower part of the crank case'by a conduit I i and to the upper part of the crank case by a A conduit l6 forming an oil reservoir and thereby preventing sudden changesof the'oil level in the. crank case. The discharge pipe IQ of the compressor is led into a condenser l1 and a pipe I the motor and to a source of current; A shutoff so the expansion valve 8.

valve 24 is provided in the branch pipe 1 ahead of I condenser isconnected to thia receiver at the pointindicated by the numeral 30. A suction:

pipe 32 which is also immersed in th fluid=2l .and which is connected to the receiver at the pointv indicated by the numeral 33. The evaporator 3 is connected to-the condenser 20 ,by a pipe 34. Q v 1 There'ceiver 2 8 -is'- provided with a float valve 35 which is connected to the liquld line I. a

The float valve 35 admits refrigerant to the v receiver 28 from'thereceiver I for compensat I mg. the;h eat leakage through the insulation-of i 4 :thecontainer 25.

. The receiver 29 is seaweed as afloat valve 36 which-may be positioned higher than the float valve is if sulphur diqxide'isused rlower the float valve as a refrigerants which v a're lighter-than 'oil.'are'.used.- Assuming that the receiver through the pipe 6 and via the sulphur dioxideisxused,the oil floats on top of the refrigerant and-..the'..;valvef36 placed at a higher'l'evel-than the valve will allow oil to pass-.from the receiver 29 via the pipe 31 to the:

oilreservoir. H, which 1 as explained before communicates with the crankcase of the compressor [2.

"The-milk cooler operates as follows: When H10 current is 'supplied'to the motor and the machine" starts up,.liquid refrigerant passes from 'valve 35 to the auxiliary receiver; 29- where it evaporates and absorbs heat from its surroundings until most oftheheat contained in'the in- 'sulated container '25 is removed and the eutectic mixture 28 is congealed. The fins 21 extend from the auxiliary. receiver 29 throughout 'the mixture 28 and in contact with the condenser 26 and are' provided both for expediting the process just ex- 'plained and for pre-condensing gaseous refrigerant duringthe process of cooling the milk.

"' j Thecontainer 25 having been reduced intemperature and the eutectic fluid 28 congealed, the

pressure in. the receiver I4 is greatly reduced and I the control 22 acts and stops the motor from opcrating. v v

"The 's ystemis thenready for the milk cooler to operate.

Cold water is passed via the bottom inlet 4 through the coil 2 and out 'via the outlet 4a. The valve 24 in the liquid line I is opened so that the thermostatically controlled expansion valve 1 may operate under control of its thermobulb I0. Y

Milk is allowed to trickle over the pipes of the -coil 2 where the temperature is reduced by the cold water flowing therethrough."-\ Aft er leaving the coil 2 the milk trickles over the'coil 3 which is the evaporator of the system. I -As soon as the valve 24 is opened, as previously described, liquid refrigerant evaporating in the coils -3 reduces the temperature thereof until the thermo-bulb l0 closes-the automatic expansion valve 8. When the-milk which is warm reaches 'these coils they are warmed up thereby, and the thermo-bulb allows more refrigerant to pass through into the 0011, thereby cooling the milk.

Gaseous refrigerant from the evaporator 3,

in seeking the coldest place, passes via the pipe 34 into the auxiliary condenser 26 which with its fins is surrounded by the frozen eutectic fluid 28, as above described. The heat from these gases is given up to the fluid 28 and the refrigerant condenses and passes down via the inlet 30 into the auxiliary receiver 29;

The control 22 is so set that when heat enters the insulated compartment 25 the motor starts and driving the compressor, pulls refrigerant from the auxiliary receiver via the connection 33, the suction coil 32 and the pipe- 3|, to the inlet of the compressor, and compressed refrigerant leaving the compressor via the pipe I 6 enters the condenser I! where it is liquified and liquid refrigerant passes therefromvia the pipe l8 to the receiveri. I

The'system' isso proportioned that when the auxiliary condenser has its temperature reduced and the eutectic fluid 28 frozen, practically all of the refrigerant is in the-main receiver 5, and when the predetermined quantity of milk has- 'been' cooled the majority ofthe liquid refrigerant is in theauxiliary receiver 29, and only a small quantity in the main receiver 5. in the quick freezing-system, as shown in Figure 2, a compressor '39, which may be-driven by any suitable source of power, is" connecte to a main condenser 40 by the pipe 4|. The con enser 40 is connected to a main receiver 42 which is of suiiicient capacity to hold substantially all of the liquid refrigerant in the-system.

- ,A liquid line 43 extends from a point near the bottom of the receiver 42 to an expansion valve 44. -15. quick freezing chamber 45, having insulated walls 45 is provided with an evaporator 41. The upper end of the evaporator 41 is connected to the expansion valve'44 and thelower end is conected by pipe'48 to an expansion valve 49 which is adapted tobe by-passed by a valve 50. An auxiliary condenser 51, having a plurality of receiver 53. a

The condenser 5|, with. its fins 52 and the auxiliary receiver 53, is'enclos'ed in a tank containing a eutectic fluid 54 andsurrounlded by a suitable insulated casing 55. A pipe. 56 connects the aux' iliary condenser 5| to the expansion valve 49 and to the by-pass valve 50. The outlet 51 of the auxiliary receiver 53 is connected to a liquid fins, one of which is designated by the 'numeral 52, has its lower coil terminatingin an auxiliary pump 58 and the outlet pipe 59 of this pump is led into the main receiver 42. In some installations it may be desirable to conect the expansion valve 49 to the liquid line 43. Such connection is shown dotted at 60, and includes a shut-ofl valve 6]. It may also be desirable to have the suction line 62 connecteddirectly to the evaporator 41, thereby by-passing the auxiliary condenser 5|. Such a connection is shown dotted at 63 and includes a shut-off valve 64.

The quick freezing room 45 may be equipped with shelves upon which goods to be frozen may be placed. The floor of the room 45 may consist of a shallow open tank 65 adapted to hold a quantity of brine. This brine is passed via the pipe 66 to the inlet of a pump 51 and the outlet 68 of the pump supplies this brine under pressure to the pipes 69 and 10. These last-named pipes are provided with a plurality of orifices one ofwhich is designatedby the numeral 1!, through which the-brine under pressure is sprayed or atomized into'the air in the chamber 45. This fine spray Q or mistof brine is cooled by the evaporator 41 and. comesin'to contact with the goods on the shelves,

absorbing heat therefrom and freezing the same.

Before starting the quick freezing action, thecompressor is operated and liquid refrigerant from the receiver 4.2 via the liquidline' 43 and the expansion valve 44 passes into the evaporator 41 and via the pipe 48, and the expansion valve 49 this refrigerant passes into the auxiliary condenser 5|, reducing the temperatures of both the fast freezing room 45 and the eutectic fluid 54 surrefrigerant leaving the auxiliary receiver 53 passes rounding the auxiliary condenser 5|; Gaseous via. the suction pipe 52 to the compressor, where it is compressed and passes via the pipe 4| into the condenser, and upon becoming liquefied therein passes into the main receiver 42. This process is continued; until the eutectic fluid 54 has'become congealed, whereupon the system is ready for the fast freezing process. 1

The motor 12 is started up and the pump 51, connected thereto begins to'pump the brine and spray the same through the orifices II in the pipes 69 and 10. The sprayed'brine is cooled by. the

evaporator 41 and the refrigerant therein begins to evaporate. This refrigerant, seeking the coldest place in the system, passes via the pipe 48 and the expansion valve 49 into the auxiliary condenser ll, that it gives its hesus to the eutectic medium. H," liqueflea and flows ,into the auxiliary receiver Ihe r'efrigerar'it compressor is started up and removes from the auxiliary condenser as much gaseous refrigerant as it (the compressor-I9) can handle. The remainder.

ofthis; gaseous refrigerant is condensed in the auxiliary condenser upon giving its heat up to the eutectic fluid. At the same time,; the brine pump 61 andthe compressor 38 were started the liquid pump 58 was'also put-into operation and by means of this pump liquid refrigerant is removed from theauxiliary receiver and pumped into the main receiver l2.

After the eutecticfluid ll all become.

- melted and its temperature raised, the refrigerant compressor 38 will normally handle.

effect of the system is of such capacity as the Therefore, the process of freezing the eutectic fluid 54 in contact with the auxiliary condenser 5| enables the system to take'care of extra capacities or peak loads at periodic intervals. I

In the milk cooling system shown in Figure 3,

the evaporator is operated flooded, instead of dry, I

as shown in Figure 1 Therefore, the main receiver is not necessary as. the auxiliary receiver may be made to serve a double purpose;

. The aerator i is provided with an-upper series of pipes 2 and a lower series of pipes'li, the latter comprising a flooded evaporator. An auxiliary condenser is provided with a plurality of fins,

one of which is designated by the numeral 15, and

an auxiliary receiver it. The auxiliary receiver is connected via pipe W to the lower coil of the evaporator '03. The upper coil of the evaporator it is-connected via the pipe 18 to the auxiliary condenser it, and is provided with a'regulating auxiliary condenser is provided with a float valve f 82 and a pipe -83 leading therefrom is connected to the bottom of the condenser 84%. The compressor 85, driven by the motor 36-, through suitable belting and pulleys (not shown) discharges compressed refrigerant via the pipe 81 into the L level in the auxiliary receiver allows the floatcondenser es.

The auxiliaryreceiver is also provided with a curve-shaped pipe til extending to a point near the upper inner surface thereof. This pipe is connected via the pipe 99 to the intake oi the compressor 85, and a mallhole 89 in the curved pipe 83 is provided to allow oil to return from the auxiliary receiver to the crank case of the compressor B5.

A suitable control 92 is connected to the suction switch in said control connects ordisconnects the motor from a source of current 93.

The a condenser and receiver are anclosed in an insulated tank 95 and the interior oi this tank is filled with a eutectic fluid at.

with the valve as closed, the compressor is operated and the temperature in the auxiliary condenser and the fluid 55 is reduced until the fluid is congealed, gaseous refrigerant passing via the curved pipe 88 and suction line QGto the compressor and the discharged'refrigerant p via the pipe 8i into-the condenser at.

Liquid refrigerant; from the condenser via the pipe 83 and the float valve 82 when the liquid valve 82 to op n. v. Dueto the fact' that the valve. It is closed, liquid in flooded evaporator Iii going on.

As soon as the temperature of the auxiliary condenser and the contents of the tank 94 have been reduced to the point where the fluid 95 has congealed, the control 92' stops the 'motor and the system is ready to be used for cooling milk.

. When the valve 88 is opened, liquid refrigerant rises in the evaporator 13 to the level of that in the auxiliary receiver and gasebus refrigerant seeking the coldest place in the system passes via the regulating valve 19 into the auxiliary condenser l l, where it gives up heat to the eutectic medium 95, is condensed, and passesinto the auxiliary receiver.

i As soon as any heat enters the auxiliary condenser the pressure therein changes and the control 82 operates and sets the motor and compressor going again. The compressor 85 removes from the auxiliary receiver as much gaseous refled refrigerant from the condenser 84 passes'via the pipe 83 and the valve 82 into the receiver 16.

The same liquid level is maintained in the receiver i6 and the evaporator I3, due-to the fact that the open pipe 11 connects the-two together.

' The system is so proportioned that when its capacity of milk has been cooled, the temperature of the contents of the insulated tank 94 and the temperature of the evaporator I3 are at substantially the same temperature level.

The system shown in Figure 4 is a modification of that in Figure 2, in which the evaporator 96 is operated completely flooded. The evaporator is placed in a quick freezing room t'l, which is an open brine tank at is provided for catching Y and retaining the brine in thefsystem. The auxprovided with suitable insulating walls 98, and

iliary condenser we is positioned above the evaporator 9t and is provided with fins it! and an auxiliary receiver M32, and surrounded by'an ln-- sulating tank 3% fllled'with a'elltectic fluid IN.

A float chamber tilt has a float valve its positioned therein and-adapted to maintain a liquid 1 level in the system, indicated by'the dotted line idlhwhich is substantially on the center line of the auxiliary receiver lot.

tothe float valve. M38 in the float chamber I65. side of the system via. a pipe 8! and a suitable Liquid refrigerant from the float chamher me via the pipe iii to the bottom coil of the evaporator so. A branch pipe H2, connected to* covered with insulation lid to insulate the same brine which will presently be on u v QHI,

did some to is provided for leading brine mm the tank so td-the suction of the pump n.

89. A motor." drives a brinepump.

connected to the spray pipes 69 and I and these =pipes'areprovidedwith afplur'ality of spray nozzles II, by 'means of which brine is sprayed or atomized throughout the entire chamber 91.

F In some cases it may be desired to lead liquid refrigerant directly into the auxiliary condenser,

in which case a pipe H9 mayextend from the liquid line IIO to the top of the auxiliary,con-' denserfl00,and' an expansion valve I and a hand shut -ofi' valve IZI may be provided. This pipe and these valves are shown dotted in the drawings. r

Before'operating-the system as a quick freezer, the valve H6 may beclosed and the compressor operated. The gaseous refrigerant passes from theauxiliary receiver via the pipe III, the

float cham r ins, and the suction pipe H8, to.

the compressor, thence to the condenser; where it is liquefied and it passes on into the receiver 4 h 20 I09. This process is continued until the entire contents of theinsulated tank I03 are so reduced in temperature that the eutectic fluid I04 therein is congealed. During the process, as the rejfri'gerant level'goes down, the float valve I06 allows liquid refrigerant to pass from the receiver I09 to the float chamber I05, 'and this liquid,

n seeking itsleveLpasses-via the pipe II2 into the auxiliary receiver I00.

, After the eutectic fluid I 04 has become con-' ge'aled the system is ready to operate as a quick freezing system, the valve H8 is opened and" I gaseous refrigerant, seeking the ,coldest place, passes into the auxiliary condenser. The compressor39 removes from the auxiliary receiver as "f much gaseous refrigerant as it can handle, and

the; remainder oiithe refrigerant is condensed by the fluid I04 and passes into the auxiliary receiver I08. As the process continues, the auxiliary condenser condenses less and less of the refrigerant, until the temperature of the evaporator 96 and that of the) auxiliary condenser I00 is practically the same temperature level. Therefore, by the use of this system, sudden or peak loads ofrefrigeration may be taken care of, even 5 though they are far beyond the normal capacity of the high side of the system.

What is claimed is? compressor, a condenser, a receiver, an evaporator, an auxiliary condenser coil and an auxiliary receiver arranged in series and. connected be-' tween-said, compressor and said evaporator, a

series of metallic flns in contact with the coils, of said auxiliary condenser and saidauxlliary receiver, an expansion valve between the receiver and the evaporator, a second expansion valve between the evaporator and-the auxiliary. condenser, an insulating casing containing a eutectic fluid surrounding the auxiliary condenser, the auxiliary receiver and said fins, and a suction line in heat exchange relation withand extendj ing from saidauxiliary receiver to said com presscr, whereby all of the gaseous refrigerant leaving the evaporator is passed through the a; auxiliary condenser and the 'auxiliary receiver finoluding that part of said gases which is not intended to be condensed. in said auxiliary condenser in order to increase the velocity of and to-- i maintain a turbulent flowof said gaseous refrig- 7 erant with a resultant high rate of heat transfer. 2; In a refrigerating system in combination, a

I compressor, acondenser, a main receiver, an

1 evaporator, an auxiliary condenser and anauxiliary receiver, a series of find in metallic contact 1 with said auxiliary condenser and said auxiliary accepts 1. In a refrigerating system in combination a receivenan insulating casing containing a eutec tic medium surrounding the" auxiliary condenser and receiver, a float valve in the' auxiliary receiver adapted to maintain .aconstant level of liquid refrigerant therein, a conduit between the au'xil iary receiver and the evaporator for'all'owingl'said' liquid to seek its level in saidevaporator, a". conduit connecting saidevaporator to 'sfaidauxiliary condenser and containing a regulating valve,and' means for storing cold in saldmedium forliquefying some gaseous refrigerant in the auxiliary.-

' condenser thereby effectively increasing the capacity of said system periodically, said auxil iary receiver serving to deliver liquid refrigerant,

from both the main and the auxiliary condensers to said evaporator. ".ji

3.. .In a refrigerating systemin combination, a compressor, a condenser connected the'reto, a receiver associated with said condenser,'an evaporator, a float chamber positioned-'above the bottom line of said evaporator and communicating said receiver to the float valvefor supplying the evaporator with said liquidQan auxiliary condenser positioned above said evaporator,- anauxtherewith, a liquid refrigerant line leading from iliary receiver associated with said auxiliary condenser so positioned that'it is normally partially filled with liquid, connections betweenfthe bottom of the auxiliary receiver, the bottom of the float chamber and the bottom of the evaporator, a pipe leading from the top of the evaporator to the top of the auxiliary condenser, a pipe leading from the topof the auxiliary receiver to the top of the float chamber, {a suction. line leading from the top of thefloat chamber to the intake of said compressor, a series of fins in metallic contact with said-auxiliary condenser and said auxiliary receiver, andan insulated container containing a eutectic medium surround-'- ing said auxiliary condenser'and receiver whereby cold may be storedtherein' for periodically increasing the effective capacity of thesystem by enabling the auxiliary condenserto liquefy-at least a portion of the refrigerant and deliver the same to the evaporator without allowing'ittoleave the low side of the'system.

4,..Iri a refrigerating "system, a compresson-a I condenser, and an evaporator, an auxiliarycondenser positioned between said evaporator-and" said compressona medium. within said casing for. storing up cold, saidmedium being adapted to v v receive heat only from articles cooled by the evaporator and via a refrigerating medium cIr culating in said system, a by-pass between said auxiliary' condenser andsaid, compressor,

means within said auxiliary condenser to deliver lubricant to said compressor vlasald by-pass,'i 5. In a refrigerating system," 'a' compressor" and means for driving the same, a condenser, an I evaporator having a B. t. u,v capacity substantially 1 greater than that of said compressor, an auxiliary condenser, a suction coil, and a receiver therebetween and a eutectic fluid in thermal relation to said receiver "and adapted'to periodically-store up cold, said auxiliary condenser and receiver being connected between said evaporator and said compressor, forminga circuit through which gaseous refrigerant must pass athigh velocity to effect emcient heat transfer-with said fluid' 'and thereby effectivelyincreasing the refrigerating capacity of the system duringfa, comparatively short'period oftime...

'6. In a refrigerating system}. acompressor, a

condenser, a main receiver, an evaporator, an

auxiliary condenser including 8.xc0lld conduit,

an auxiliary receiver, a series of metallic'flns in thermal contact with K d conduit and said auxiliary receiver, .a storage medium in contact with said conduit, said auxiliary receiver, andsaid 'flns; said auxiliary condenser and said auxiliary.

receiver being connected in series and associated with the. suction end of the evaporator and with the intake of said compressor so thatall gaseous refrigerant leaving the evaporator will pass through said auxiliary condenser and said auxiliary receiver with suiiicient velocity and'tur bulence to effect a high rate of heat transfer between said refrigerant and said medium. s

7. In a refrigerating system, a compressor, a condenser, a main receiver, an 'evaporatonan auxiliary condenser including, acoiled conduit, an auxiliary receiver, a-suction .0011; a series of metallic fins in thermal contact with said conduit, said suction coil, and said auxiliary receiver; a storage medium in contact with said conduit, said auxiliary receiver, said suction coil, and said' fins; said auxiliary condenser, said suction coil, and said auxiliary receiver being connected in series and associated with the suction end of the evaporator and with the intake of said, compressor so that all gaseous refrigerant leaving the evaporator will pass through said auxiliary condenser and said auxiliary receiver with sumcient velocity'and turbulence to effect a high rate of heat transfer between said refrigerant and said medium.

8. In a system of the character described, including an evaporator, a condenser, a main receiver, and'a compressor; an auxiliary condenser positioned between the evaporator and the intake of said compressor comprising-a coil, an auxiliary receiver, a series of tins in thermal contact with said coil and with said auxiliary receiver; a storage medium embracing said coil, said auxiliary receiver and said fins; and an insulating casing surrounding said medium; said coil and said auxiliary receiver being connected in serieswhereby all gaseous reirigerant fronr the evaporator may passtherethrough at a high velocity to effect a high rate or heat exchange between said refrigerant and said medium.

9. In a system of the-character described, including an evaporator, a condenser, a main receiver, and a compressor an auxiliary condenser positioned between the evaporator and the intake of said compressor comprising an auxiliary con.- densing coil, an aumliary receiver, a suction coil, a series of fins in thermal contact with said coils and with said auxiliary receiver; a storage medium embracing said coils, said auxiliary receiver and said-fins;' and aninsulating casing surrounding said medium; said auxiliary condensing coil and said auxiliary receiver and said suction coil being connectedin series whereby all gaseous refrigerant from the evaporator may pass therethrough at a high velocity to efiect a high rate of heat exchange between said refrigerant and said medium. Y

10. In a refrigerating system, a cooling unit, a compressor, a condenser, a receiver associated with one end of said cooling. unit, and an auxiliary condenser and auxiliary receiver connected in series between the other end of said cooling unit and the intake of said compressor, a eutectic fluid surrounding said auxiliary condenser and saidauxiliary receiver and adapted to store cold to. take care of peak loads on said system, said auxiliarycondenser being adapted to refrigerate the system.

11. In a refrigerating system, a cooling .unit, a

compressor, a condenser, a receiver associated with one end of said cooling unit, and an auxiliary condenser and auxiliary receiver connected ,in seriesbetween the other end of said cooling unit and the intake of said compressor, a' eutectic fluid surrounding said auxiliary condenser andsaid auxiliary receiver and adapted to store cold to take care of peak loads on said system, a liquid line leading fromsaid. receiver to saidauxiliary receiver, and a liquid line leading from saidauxiiiary receiver to said evaporator, saidauxiliary cdndenser being adapted to refrigerate said unit during a portion of the time, and said compressor and said auxiliary condenser being adapted conjointly to refrigerate said unit during other partions' of the time. Y

'12. In a refrigeratingsystem, a cooling unit, a compressor, acondenser, a receiver associated with one end of said cooling" unit, and an auxiliary condenser and auxiliary receiver connected in series between the other end of said'cooling unit and the intake of'said compressor, a eutectic fluid surrounding said auxiliary condenser and said auxiliary receiver and adapted to store cold i to take care of peak loads on said system; said auxiliary condenser being adapted to refrigerate said unit during a portion of thejtime, and said compressor and said auxiliaryTcdnden-ser being 1 adapted conjointly to refrigerate said 'unit during other portions of the tiine, the liquid from said receiver being reducedto a low. temperature in said auxiliary receiver before it reaches said evaporatonthereby increasing the efliciency'iof 13. In a refrigerating system, a cooling unit, a

compressor, a condenser, a receiver associated.

with one end of said cooling unit, and an auxiliary condenser and auxiliary receiver connected in series between the jother end of said cooling unit and the intake of said compressor, a eutectic fluid surrounding said auxiliary condenser and said auxiliary receiver and. adapted to store cold .to take care of 'peak loads on said system, said, auxiliary condenser being adapted to refrigera said unit during a portion of the time, and said compressor and said auxiliary condenser being adapted conjointly to refrigerate said unit during other portions of the time, said auxiliary receiver serving to precool liquid refrigerant delivered to the evaporator, the flash gas being separated in theauxiliaryreceiver, thereby providing a highly eficient system.

14. In a refrigerating system in combination with a compressor, a condenser, a receiver, an

evaporator, a float chamber communicating with I the other endof said evaporator, the other .end of said auxiliary condenser being connected to said auxiliary receiver, a connection between the auxiliary receiver and said float chamber, a con-, nection between the intake of said compressor and said float chamber, a connection between said receiver and said float chamber-including a float valvein said chamber for controlling the admission ofliquid refrigerant thereto from said receiver, a connection between said auxiliary receiver. and said first end ofsaid evaporator whereby liquid refrigerant condensed due to heat exchange with said medium may return to said evaporator without reaching said compressor.

15. In a refrigerating system in combination with a compressor, a condenser, a receiver,- an

evaporator, a float chamber communicating with one end of said evaporator, an auxiliary condenser and an auxiliary receiver metallically connected together by. radiating plates," and surrounded by an insulating casing containingja storage'medium, connections between one end 10f said auxiliary condenser and the other end of said evaporator, the other end of said auxiliary condenser being connected to said auxiliary receiver, a connection between the axuiliary receiver and said float chamber,-"a connection between the inake of said compressor and said float chamber, a' connection between said' receiver and said float chamber including a float valve in said chamber for controlling the admission 0f liquid refrigerant thereto from said receiver, a connection between said auxiliary receiver and said first end of said evaporator whereby liquid refrigerant condensed due to heat exchange with said medium may return to said evaporator without reaching said compressor,-and means for spraying brine about said evaporator.

16. The invention according to claim 15, in

which shut-off means is included in the connec tions between said end of the auxiliary condenser and said other end of the'e'vaporator, and in which an expansion valve is provided for delivering refrigerant from the high side to said auxiliary condenser.

17. In a refrigerating system, a high side, an?

expansion valve, a plurality .ofeyaporators'each having one end connected to said valve to receive liquid refrigerant therefrom in parallel-and H having their other ends interconnected to form a,

gaseous refrigerant path through said'evaporators in series and leadingto the intake of said highsida 18. Ina. refrigerating system including a high side, an evaporator, an auxiliary. condenser connected to said evapor'ator and forming a portion of the low side insaid system, said'auxiliarycdnw denser'being "comprised of a continuous coiled,

conduit and an auxiliary receiver positioned adjacent thereto and interconnected therewith by means of a series of heat conductive fins, and an insulating casing surrounding said auxiliary condenser 'and receiver, and containing a eutectic fluid in thermal-contact with the entire surface of said conduit, said receiver and said fins.

19. In a refrigerating system including a high side, an evaporator. an auxiliary condenser connected to said evaporator and forming a portion of the low side in said system, said auxiliarylcondenserbeing comprised of 'a continuous coiled conduit. and an auxiliary receiver positioned adjacent thereto andconnected'to one end thereof,

' a suction coil positioned adjacent tosaid conduit and having one, end thereof connected to said auxiliary receiver, a series of heat conductive fins in metallic contact with said conduit, said auxiliary receiver and said suction coil and an insulating casing surrounding said auxiliary con denser? said receiver, and said'coil, and contain-' inga eutectic fluid .in thermal-contact with the entire surface of said conduit", said receiver, said fins, and said suction coil.- 

